Mercer CountyPower Outage History
2015–2025 · Missouri
Top 20% most reliable nationally — infrequent, short outages. This county ranks in the most reliable fifth of all US counties in our dataset, based on 12 years of real DOE outage records: outages happen less often here, and when they do occur they tend to be resolved quickly compared to the rest of the country. Baseline outage risk is low, though a severe local storm can still occasionally cause a longer-than-usual outage regardless of the long-term track record.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| May 17, 2019 | <1 hr | 86 (4%) | Unnamed event |
| Aug 18, 2020 | 4 hrs | 62 (3%) | Unnamed event |
| Mar 27, 2025 | <1 hr | 61 (3%) | Unnamed event |
| Jan 9, 2024 | 4 hrs | 60 (3%) | Heavy Snow |
| Aug 15, 2024 | <1 hr | 60 (3%) | Unnamed event |
Over the 11 years from 2015 to 2025, Mercer County recorded 51 distinct power outage events, averaging 1.8 hours per event.
The single worst outage on record in Mercer County started May 17, 2019, lasting less than 1 hour and leaving up to 86 customers without power (4% of the county) at its peak.
August has historically been the worst month for outages in Mercer County, with 11 events recorded during that month across the dataset.
Based on this history, Mercer County earns a Reliability Grade of A, placing it in the 98th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Mercer County's outage profile
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Read our mission →Similar counties in Missouri
Counties with the closest reliability grade and national percentile to Mercer County.
| County | Grade | National percentile |
|---|---|---|
| McDonald County | A | 97th |
| Boone County | A | 97th |
| Marion County | A | 96th |
| Putnam County | A | 96th |
| Callaway County | A | 95th |
Most reliable counties in Missouri
The top 3 counties in Missouri by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Mercer County | A | 98th |
| McDonald County | A | 97th |
| Boone County | A | 97th |
Least reliable counties in Missouri
The bottom 3 counties in Missouri by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| St. Louis County | F | 10th |
| Reynolds County | F | 20th |
| Iron County | D | 22nd |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Mercer County?
Between 2015 and 2025, Mercer County recorded 51 outage events, averaging 1.8 hours each.
What is Mercer County's reliability grade?
Mercer County has a Reliability Grade of A, in the 98th national percentile.
What was the worst power outage in Mercer County?
The worst outage on record started May 17, 2019, lasting less than 1 hour and affecting up to 86 customers.